Calculating machine



Jan. 28, 1941. M. LOTHROP CALCULATING MACHINE Filed May 27, 1935 INVENTOR.

Patented Jan. 28, 1941 UNITED STATES PATENT 2,229,895 CALCULATING MACHINE Marcus Lothrop, Berkeley, Calif assignor to Friden Calculating Machine Co. Inc, Oakland, Calif., a. corporation or California Application May 27, 1935, Serial No. 23,513

7 Claims. (on. 235-61) My invention relates to calculating machines through any standard instrumentality (diagramof the power driven type, for performing addimatically represented by line 23) to condition tioh, subtraction, multiplication and division, and the actuator H so that a corresponding efiect is particularly concerned with means for clear- Will be had ultimately in one of the registers 5 ing or zeroizing the registers of such machines. 8 and 9. Curr nt for the operati n f the m t r a An object of m invention is to provide an I8 preferably comes from electric mains 2'3 and improved means for zeroizing or clearing a regisr p v m-a is carried y a lead 2? t tcr in a calculating machine. one side of the motor l8 and by a lead 28 through The foregoing and other objects are attained switch contacts 9 n 3 p v y, to h in the embodiment of the invention illustrated other side f h m Th n s 29 a 10 in the drawing, in which the figure is a diagram- 3! are normally open, but can be resiliently closed matic view showing schematically a calculating to energize e motor y the manual p s machine constructed in accordance with my inn of a key 32 with resp t o e COVE! Plate vention. 33 on the frame 6. Thus, when the key 32 is I In its preferred form, the calculating machine p es it energizes the motor l8 to introduce 15 of my invention includes a register which is P s 1 e tive Va ues i o e registers 3 altered from zero position by a. manually conand 9. The key 3 an be designated s motor trolled, power actuated means, the actuation of bar or motor key and represents either a "plus which preconditions a zeroizing or clear mechkey, a minus key, or any other controlling 29 anism, preferably power operated, which is then key customary in calculating machines, which efiective upon th manual t ti of th is effective to introduce either positive or negative instrumentality to clear or reset the register to Values 111110 the Isgistsfzero. In order to clear such'values from the registers While the calculating machine of my invn- 8 and 9, 1m t r w rds, t r ur su r s tion is susceptible to a wide range of variations, ters to a zero indication, or to z e ch ree- 25 I have illustrated it herein diagrammatically as lsters, each of them is prefera Provided with being of the Thomas type, The stru t a clear bar such as 35 and 35, each of which cludes a frame 5 which is stationary d t is translatable under the influence of a thumb respect to which a carriage 1 is relatively movbutton Bush as 37 which, Whsn e C e 3o able, preferably being laterally translatable with bars are translated thereby. serves t sell b respect to the frame 8. The carriage carries registers 8 and 9 to zero, eithe simultaneously a pair of registers 8 and 9 respectively, in acor individually, as the individual clear bars may cordance with usual practice. Each of these be operated.

35 registers is made up of a luralit of numeral In ord n e with my invention. I p f r bly 35 wheels H and 12, each bearing suitable indlcia P e means f Zeroizing either 300th f 13 and H. The carriage 1 is translatable by these ter u 37 after Values, either 9 suitable means, such as the hand button 56, and tive or negative, have been introduced into such values are introduced into the registers 8 and egi ters; t is to s y, I preferably arrange 40 9 either directly by an actuator l! or indirectly matters in such a Way that speratifln a ea 40 thereby through an intermediate mechanism (hot y i l e fi v p the clear or Zeroizing shown), dependent upon the number of cycles me h ni m unl s h m hanism has n pr of operation of the actuator l1. Preferably, the nditi n d y t p r operation f an instruactuator is located on the frame 8 and is driven mentality such as the 111-01701 key from a source of power such as an electric motor To this t carriage 1 is P ly D O- l8 likewise located on the frame nd coupled vlded with duplicate clear mechanisms, and since thereto by suitable gearing l8 and shafting 25. they are identical but one need be described in The actuator l! is simply representative and detail. That is to say, the register a, for inmay include any number of actuating units for stance, which is cleared by translation of the so any number of different orders in the machine' clear bar 34, has associated with it and located Preferably the effect of the actuator I'l upon on the carriage l, a source of power such as the at least one of the registers 8 and 9 is directly solenoid 39. The solenoid 39 when energized is under the control of any selectable one of it effective to translate the clear bar 34 against the plurality or series of manually operable keys 22 urgency of a spring M and to zeroize the register arranged in order on the frame 6 and effective 8. Upon de-energization of the solenoid 39, the

clear bar is released and, under the influence of the spring 4|, returns to its former position, with the register remaining cleared.

In order that the solenoid 38 can be suitably energized, but only after previous operation of permits current to flow, despite relative movement between the carriage l and the frame6, to the coil of the solenoid 39, from whence the current flows to a contact point 46, to a wire 3?,

and through another flexible conductor 38, to a lead 49. From this lead a flexible conductor El extends to a contact 52 mounted on an insulating base 53 on a key shank 56. This key shank is depressible with respect to the cover plate 33 by actuation of a finger button 56, and is nor- 6% against the urgency of the spring 6?.

mally maintained in uppermost position by a coil spring 51, As thus far described, the electric circuit is open and stopped at the contact 52, so that depression and release of the key button 56 simply serves to translate the key shank.

54 and is ineffective to energize the solenoid 39 to clear the register. The register clear key 56, therefore, is ineffective upon a single manual. stroke, but the clear mechanism must be preconditioned to be effective to clear the register. To this end I preferably provide a preconditioning mechanism which is afiected by the motor key 32. The motor key carries a pawl plate 58 which is mounted on a pivot 59 fixed on the shank B6 of the key 32, and is normally held against a stop pin 6| by a relatively light spring 62. The pawl plate 58 travels in the same plane as a slide 63 which is constrained'to translation on the frame 6 by stationary pins 64 and 66 respectively. A coil spring 61 normally urges the slide 63 into a position in the path of the pawl plate 58.

Upon initial depression of the key 32, the pawl plate 58 yields against the projected slide 63, which is held by its relatively strong spring 61, until key 32 has completed closing the contacts 29 and 3| and pawl plate 58 has moved under slide 63. Whenthe key 32 is manually released,

however, and the key shank 68 is returned under the influence of its spring 5'8 the pawl plate 68 is prevented from yielding in a clockwise direction by the stop P l 65 and translates the slide The slide must be fully translated before the pawl plate 553 can ride out from under the nose of the slide 63 and return to its initial position. This complete translation of slide permits a latch 68 to interengage with a notch in the slide 63. The latch 68 is part of a lever l'l which is pivoted on the frame, as at 52, and is normally urged into latching position by'a coil spring '53. Thus, the return of the key after being depressed to energize the motor l is efiective to cook or latch the slide 63. Any number of subsequent depressions of the key are ineffective upon the slide 63 in its latched position, and the motor l8 can be energized any numberof times without in anywise ,afiecting the slide 63.

When, however, it is desired to operate the clear mechanism which has thus been preconditioned, depression of the key 56 moves the contact 52 toward the slide so that it passes by without touching a contact l5 mounted on an insulator 16 on the slide 63 and connected by a flexible conductor ill to a lead l8 joined by a wire 19 to the main 26. That is, if the contact points 52 and 15 were abutted, the circuit would be closed." However, depression of the key 56 does not directly abut the contacts 52 and I5, but the key 56 must be depressed sufficiently far so that the end of its shank 54 contacts a pin 8| at the extremity of the lever ll. The lever is then rotated about itspivot [12 to unlatch the slide 63 which, under the urgency of its spring 61, translates the contact E5 to lie in the path of return of the contact 52. Thus, when the key 56 is released, the superior urgency of the spring 51 lifts the contact 52 to abut the contact l5, which is moved slightly in a direction to recompress the spring 61 and momentarily completes the circuit to the solenoid 39. The key 56 returns to its original position, and the slide 63 likewise returns to its original unlatched position with the contacts 52 and apart. There has thus been a momentary energization of the solenoid 39, to efiect a clearing of the register 8.

This momentary closure of the circuit may or may not be suflicieht to complete the clearing 4 operation. If it is not sufficient, the momentary and 88 are closed and the current is maintained indefinitely. This same energization of the solenoid is also eifective to draw the clear bar 34 into the solenoid, and the translation of this bar continues until completion of the clear operation. At the end of the necessary movement, a hammer 92 at the extremity of the bar bends the spring 81 to push the contact 88 away from the contact 46 and to interrupt the circuit. Thus, for clearing the register 8 it is .first essential that the motor key 32 be depressed and released in order to precondition the clear mechanism. After the mechanism is once preconditioned it remains in such state until depression of the clear key 56, release of which initiates the clearing operation which proceeds through its cycle to completion and at the end of which time the parts are all restored to their original condition and the register 6 cannot again be cleared until after a subsequent depression and release of the 7 ing contacts we, flexible conductors M3, and

leads Mi l and E65, which are connected in the circuit as described in connection with the mechanism for the register 8 and extend to a control key till which is preferably located in the frame alongside the key 56 and is connected to identical mechanism. It is usually preferred that the preconditioning of the mechanism for the key till] be controlled by the motor key 32 which for that purpose is preferably provided with another and duplicate member (not shown) corresponding to the pawl lever 58 but operating in the path of a slide (not shown) appurtenant to the key .idl That is to say, depression and subsequent release of the motor key 32 preferably preconaaeasee ditions both of the mechanisms each associated with the keys 56 and till, so that either orboth of the registers can subsequently be cleared. Thus, while one register can be cleared after an actuation of the motor key 32, the other register can be cleared at any time after the original operation of the motor key 32 and without waiting for a subsequent operation thereof.

Either the key 56 or the key 32 can be depressed at any instant, but they cannot be de: pressed simultaneously, beingprevented by an interlatch in the form of a bar I08 freely slidable on the cover plate 33 which is translated by lugs I09 and III upon initial movement of either key to interengage with the shank of the other key to hold it momentarily against inadvertent depression. A centralizing spring 'I I2 restores the bar I08 to neutral position.

The described mechanism is especially applicable to a calculating machine in which the carriage is movable with respect to the frame on which the key instrumentalities are mounted, and in which the source of power, such as the solenoids, is mounted on and movable with the carriage itself, thus facilitating, by means of easily broken electrical connections, the complete removal of the carriage from the frame without the necessity of breaking any difficult mechanical connections. Under no circumstances, fur thermore, is it possible to zeroize or clear the register until after either positive or negative values have been introduced therein; or, in other words, it is never possible to clear either or both registers by a single manual stroke, it requiring always a' preconditioning stroke and subsequently an energizing stroke.

For a complete disclosure of the type of ma chine to which my invention is especially applicable, reference is made to the co-pending application of Carl M. Friden, Serial No. 724,482, filed May 8, 1934.

I claim:

1. A calculating machine comprising a register, means for zeroizing said register including a depressible key and normally disabled means settable for control by depression of said key but normally unresponsive to depression thereof, and means including a manually actuated key for enabling said normally disabled means to respond to the control of said depressible key.

2. A calculating machine comprising a register, means for zeroizing said register including a depressible key and normally disabled means controlled by depression of said key, means including a manually actuated key for enabling said normally disabled means, and means controlled by said normally disabled means for effecting latching thereof in active position.

3. A calculating machine comprising a, register, means for zeroizing said register including a depressible key and normally-disabled means controlled by depression of said key, means including a manually actuated key for enabling said normally disabled means, means controlled by said normally disabled means for efiecting latching thereof in active position, said latching means being related to said depressible key for movement thereby to inactive position.

4. A calculating machine comprising a frame, a register translatable with respect to said frame, key-controlled means on said frame for introducing values into said register, meansfor zeroizing said register, normally ineffective key-actuated means on said frame for energizing said zeroizing means, and means controlled by said key-controlled means for rendering said key-actuated means effective.

5. A calculating machine comprising a register, means for zeroizing said register, control means for said zeroizing means including a plurality of movable control elements, means responsive to movement of at least two of said control elements for determining operation of said zeroizing means, means for introducing values into said register and moving one of said control elements, and means including a manually actuated key for moving another of said control elements.

6. In a calculating machine, actuating means, a register for operation by said actuating means, power-operated means for zeroizing said register, normally disabled manually operable control means for controlling operation of said zeroizing normally in an inactive position and movable therefrom to an active position, whereby manual operation of said control means normally is inefi'ective, means for initiating a machine operation, and means controlled by said operation initiating means for enabling said control means by movingsaid element to active position.

MARCUS LOTHROP. 

